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Smallpox Virus Definition and History
An illness resulting from infection with the variola virus. Though smallpox was once a much-feared and leading cause of death worldwide, aggressive vaccination efforts resulted in the World Health Organization’s determination of its eradication as a naturally occurring disease in 1980.
The last smallpox infection to occur in the United States was in 1949; the last smallpox infection in the world was in 1977 (Somalia).
The name derives from the characteristic appearance of small sores that blister and then crust, or pox, on the body when illness emerges. The sores, along with fever, are the primary symptom. They are also the means by which the virus sheds; contact with the sores or the fluids they contain spreads the virus and the infection.
Throughout history until its eradication in the 20th century, smallpox claimed the lives of a third of those infected and often left disfiguring scars on those who survived.
Because the risk for complications is relatively high with the smallpox vaccine and there are no smallpox infections worldwide, routine vaccination for smallpox no longer occurs. Smallpox reemerged as a potential public health concern in the early 2000s with worries that it, along with other infectious pathogens such as anthrax, could be used as a biologic weapon or bioterrorism agent.
Governments around the world have prepared emergency response plans to cope with such potential actions. Though when smallpox occurred naturally as a disease there were no known treatments, researchers believe modern antiviral medications would be effective against smallpox infection today.
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